PDP Authentication Failure

I had issues with my service earlier this week and thought it would be something through AT&T as it related to service. I spent several hours at AT&T watching them try everything from replacing SIM cards to speaking with several internal I.T departments. It got to the point I left my phone and came back at the end of day to only learn it’s a known issue with iPhone 12’s. I was told everything was attempted from what they read online and I even tried things I could find to support solving this issue. What is the deal, why is there not an update to solve this problem? My phone is under warranty, can I get a replacement?

thank you for your help, this is just frustrating.